Method of evaluating paper toweling or the like



y 3, 1949. J. SOBOTA 2,469,013

METHOD OF EVALUATING PAPER TOWELING OR THE LIKE Filed Jan. 19. 1948 Patented May 3, 1949 METHOD OF EVALUATING PAPER TOWELING OR THE LIKE John Sobota, Green Bay, Wis., assignor to Fort Howard Paper Company, Green Bay, Wis, a corporation of Wisconsin Application January 19, 1948, Serial No. 3,015

- 2 Claims.

1 This invention relates to improvements in the method of evaluating paper toweling or the like. There are three important characteristics which, when found together, identify high grade paper toweling. The first of these is the towels ability to rapidly absorb liquids with which it comes in contact, and the second of these is the ability of the towel to absorb said liquids evenly throughout its extent. Generally, poor absorption qualities or the existence of areas of low absorption greatly decrease the efliciency of the towel and are a source of considerable inconvenience to the user. 4

The third characteristic of high grade toweling is its ability to resist being torn or broken after it has absorbed a quantity of water. This latter characteristic is what is known as wet strength. High wet strength is very desirable for the reason that toweling which does not possess this characteristic is susceptible of being easily torn or of literally falling apart upon absorption of a quantity of water or other liquid. This not only makes the towel dimcult to handle and use, but, in addition, results in portions of the towel being deposited on the skin of the user,

which portions are difficult to remove. For these reasons it is evident that a towel of low wet strength is also a source of great inconvenience to the user.

As hereinbefore discussed it is of utmost importance that a paper towel, in order to give the highest degree of satisfaction to the user, possess high absorption speed, uniformity of absorption, and high wet strength. A towel lacking in any one of these characteristics is objectionable and is not considered to be of highest quality.

In order, therefore, to properly evaluate the quality of a given sample of paper toweling, it is necessary to test said sample for each of the three desired characteristics, and it is particularly desirable to be able to quickly and easily perform these tests at any convenient place, without the use of complicated laboratory equipment.

It is therefore a general object of the invention to provide an improved method of evaluating paper toweling or the like, which method includes tests for speed of absorption, for uniformity of absorption, and for wet strength.

A further object of the invention is to provide an improved method of evaluating paper toweling or the like which may be performed by a minimum of steps and without the use of complicated laboratory equipment.

A further object of the invention is to provide a method of evaluating paper toweling or the 2 like which may be performed quickly and easily and in any convenient place.

With these and other objects in view, the invention consists of the improved method of evaluating paper toweling or the like and all of the steps incident thereto, and all equivalents thereof.

A clear conception of the several steps of my improved method may be had by referring to the drawing accompanying'and forming a part of this specification, wherein like reference characters designate the same parts in all of the views:

Fig. 1 is a perspective side view of a piece of paper toweling or the like, together with a pair of telescopic hoops showing the toweling about to be assembled therewith;

Fig. 2 is a side perspective view showing the section of toweling of Fig. 1 framed by the telescoping hoops of Fig. l, the latter being in assembled relationship;

Fig. 3 is an enlarged, fragmentary vertical sectional view taken along the line 33 of Fig. 2;

Fig. 4 is a perspective view of the assembly of Fig. 2 inverted and placed in a pan, the bottom of the latter being covered with water; and

Fig. 5 is a perspective view of the assembly of Fig. 2 removed from the pan of Fig. 4, the assembly being placed on a supporting stand, and there being test weights on the toweling.

Referring more particularly to Fig. 1 of the drawing, the numeral it indicates a sheet of paper toweling or the like, the characteristics of which are to be evaluated. The first step of the improved evaluation method is to mount the sheet ill! in a suitable frame, such as the frame l l. The latter comprises a pair of telescopic hoops I 2 and i3. The hoops l2 and I3 are preferably formed with outwardly projecting heads M at their upper and lower edges (see Fig. 3), the inner hoop l 2 being preferably provided on its outer face with a layer of cork or similar material l5 between the beads M. In addition, the outer hoop l3 may be provided with a spring loaded expansion joint it. To mount the sheet ill it is laid over the hoop l2, and the hoop it is placed on top of the sheet ill in registration with the hoop I2. Downward pressure on the hoop l3 causes it to telescope down over the hoop It with the towel ill interposed therebetween. In drawing the hoop it over the hoop l2, the towel H) is pulled until the drumhead portion thereof within the frame H is relatively taut. The spring of the expansion joint it causes the hoop It to tightly encircle the hoop it and the portion of the towel it drawn thereover. The outwardly extending edges of the paper 3 are then trimmed off adjacent the frame H as shown in Figs. 4 and 5.

To perform the first test in the evaluation of the sample of toweling ID, a small amount of water suflicient to cover the bottom is placed in a suitable pan I! having a. diameter larger than that of the frame II. The frame Ii carrying the paper In is then brought, paper side down, over the water in the pan ll. The frame I I and towel I are then lowered toward the surface of the water in the pan' l1 and are brought in contact therewith (as shown in Fig. 4) in such a manher that at the instant of said contact the plane of the paper In is substantially parallel with the plane of the surface of the water in the pan II. From the instant of contact of the towel ID with the water in the pan II the towel ill will begin to absorb the water due to capillary action. The speed with which the samplev of towel l0 absorbs the water can be readily observed and compared with the speed of absorption of other samples under like conditions. Generally speaking, the higher the speed of absorption, the better the quality of the towel. Simultaneously, with the observation of the speed of absorption of the sample, observation can be made of the uniformity with which the sample absorbs over its entire water-contacted area. Non-uniformity of absorption usually indicates that the sample of toweling is not homogeneous in substance and, hence, is not of high quality.

After the sample of toweling III has been wet, the frame ll, along with the towel I0, is removed from the pan and placed on a suitable support such as the stand 18. The stand l8 may consist of a round base member I9 provided with upright leg members 20 projecting therefrom and positioned adjacent the periphery of the base IS. The legs 20 are preferably formed with notched out portions 2| on the inner side of their upper ends, which notches provide shoulders 22 spaced downwardly from the upper ends of the legs 20 and on which the frame ll may be supported.

The wet strength of the sample I0 can now be tested by placing on the center thereof, as shown in Fig. 5, a sufficient number of weight discs 23 to cause a breaking of the discs through the towel [0. Initially, only one weight disc 23 is placed on the wet towel l0, and then additional single weight discs 23 are placed on top of the first weight disc until the breaking point is reached. The number of discs 23, each of predetermined weight, which are necessary to cause a breaking of the towel I0, is a measure of the wet strength of the towel. This number may be readily compared with the number of discs 23 necessary to cause the breaking of a sample of other toweling under the same conditions. The greater the amount of weight as above determined, which can be sustained by a sample of wet toweling Hi, the greater its wet strength.

A round frame ll used in conjunction with weights having a round contacting surface area has been found to give the most accurate results. This is because of the fact that the round shape of the weights coacting with the round shape of the frame causes the sample of toweling being 4 tested to be stressed uniformly. As a result, said sample will sustain a maximum amount of weight before fracture, since there are no points of abnormal stress which might cause premature fracture and erroneous results.

From the foregoing it will be observed that the invention provides a quick, easy and novel method of evaluating a sample of paper toweling by testing the quality of its three basic characteristics. No elaborate laboratory equipment is necessary, the equipment used being simple and portable, and permitting the performance of the evaluating tests at any convenient place.

Various changes and modifications may be made without departing from the spirit of the invention, and all of such changes are contemplated as will come within the scope of the claims.

What I claim is:

1. The method of evaluating paper toweling or the like including the steps of supporting a circular extent of the toweling on a frame by engaging the peripheral portions thereof with said frame in such a manner that the portion of the towel within the engaged peripheral portions thereof is relatively taut and lies in substantially one plane only, then wetting said last mentioned portion of toweling, then supporting the frame in a horizontal plane, and then applying to the toweling at substantially the center thereof a progressively increasing number of weights of substantially the same shape as the portion of the toweling within the frame until the breaking point of the toweling is reached.

2. The method of evaluating paper toweling or the like including the steps of supporting a circular sheet of toweling on a frame by engaging the entire peripheral area of the toweling with said frame in such a manner that the portion of the toweling within said engaged periphery thereof lies in substantially one plane only, then bringing said portion of the toweling within the frame into contact with the surface of a body of water in such a manner that at the instant of said contact the portion of the towel within the frame and the surface of the water are substantially parallel, then supporting said frame and towel in a horizontal plane, and then applying a progressively increasing predetermined weight on a predetermined area of the central portion of said toweling until the breaking point of the toweling is reached.

JOHN SOBOTA.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 292,130 Morrison et al. Jan. 15, 1884 2,294,511 Neiman Sept. 1, 1942 2,329,959 Van Den Akker Sept. 21, 1943 2,369,661 Dangelmajer Feb. 20, 1945 FOREIGN PATENTS Number Country Date 687,819 France May 5, 1930 

